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Deployment

For all methods and hardware platforms, see the official SGLang installation guide. The two paths below match the Python / Docker toggle in the command panel.
Command
Then run the Python output of the command panel below in that environment.
Pick your hardware, precision and strategy to generate the launch command. Every recipe runs on the recommended (smallest) GPU count with SGLang’s defaults plus --max-running-requests 256; size --max-running-requests and --context-length to your own workload.
  • Low-Latency: ECHO speculative decoding (2 draft steps). Fastest replies for a single user or light load.
  • High-Throughput: attention DP without a draft. Most tokens per second across many concurrent requests.
The single-node FP8 recipes are verified on B300, GB300, B200, GB200 and H100, as are the BF16 recipes on B300; the other BF16 recipes follow from the same memory budget and are not yet verified.

Playground

The Playground is where you experiment with SGLang features beyond the verified matrix. The Deploy panel above only emits combinations the SGLang team has signed off on; the Playground lets you turn on additional knobs on top of whichever cell the Deploy panel is currently showing.

1. Model Introduction

ERNIE-5.5-Flash is Baidu’s sparse Mixture-of-Experts language model with 280B total and 14B activated parameters per token, pre-trained from scratch on 33.5T tokens with a training context of up to 128K. It comes as two models: ERNIE-5.5-Flash-Base (FP8 and BF16), taken at the end of pre-training before any mid- or post-training, a starting point for domain adaptation, instruction tuning and reinforcement-learning research, served through the completions endpoint; and ERNIE-5.5-Flash (FP8 / FP4 / BF16, coming soon), with reasoning, tool calling and a bundled DSpark draft. Its 43 layers are 1 dense FFN layer plus 42 Multi-Router Latent MoE layers. Attention is hybrid: 37 layers use Heavily Compressed Attention (HCA, one cached entry per 128 tokens plus a 128-token sliding window, 512-dim heads) and one in seven, 6 layers, keep full-context access through MLA with DSA sparse attention (256-dim heads). Every attention layer adds a low-rank output gate, Virtual Head Attention (a low-rank post-mix across heads) and QK-norm. Each MoE layer has 512 routed experts (top-10) plus 1 shared expert in a 2048-d latent space, selected by several sigmoid routers. Manifold-constrained hyper-connections (expansion rate 4) replace the residual stream, a MultiMax head produces the logits, and ECHO reuses the final layer as a one-step speculative draft. It is released under the Apache-2.0 license.
ModelWeightsUse
ERNIE-5.5-Flash-BaseFP8 / BF16Base model, completions. Released
ERNIE-5.5-FlashFP8 / FP4 / BF16Chat, reasoning, tool calling, DSpark. Coming soon
All checkpoints share the architecture above: 280B total / 14B activated parameters. Total parameters include the input embedding and the output head; activated parameters count the output head but not the embedding lookup. Both exclude the 0.36B ECHO parameters. The model was trained with a context of up to 128K tokens (131,072); fine-tuning and inference support up to 1M (1,048,576); pass --context-length 1048576 to use it. Sampling defaults: temperature=1.0, top_p=0.95 (from the checkpoint’s generation_config.json); pass temperature=0 for greedy decoding. Resources: Hugging Face, ModelScope, ERNIE-5.5-Flash-Base technical blog.

2. Configuration Tips

  • What gets set automatically. The model selects the ernie55 attention backend, --page-size 256, and --swa-full-tokens-ratio 0.1 on its own. --kv-cache-dtype defaults to fp8_e4m3; bfloat16 is the only other supported value.
  • Parallelism. Attention TP (tp / attn-dp-size / attn-cp-size) must divide 8, the number of output groups. The high-throughput recipes use attention TP 1 (--attn-dp-size equal to --tp); the low-latency recipes use plain TP, except BF16 on H100, where TP 16 keeps --attn-dp-size 2 so attention TP stays at 8. Expert parallelism is optional: --ep N --moe-a2a-backend deepep routes experts over DeepEP, which needs --ep 4 or more (at --ep 2 each rank would hold 256 experts, past DeepEP’s per-rank limit). Prefill context parallelism (--attn-cp-size N --enable-prefill-cp --cp-strategy interleave) and pipeline parallelism also work; under PP use --moe-a2a-backend none.
  • Long context. The released config allows 1,048,576 tokens. Pass --context-length 1048576, and lower --max-running-requests (to single digits on 2 × B300) and --cuda-graph-max-bs-decode: each rank’s KV pool must hold whole 1M-token requests, and a 1M prefill needs tens of GB of activation memory on top.
  • DeepEP. When you add --moe-a2a-backend deepep, decode runs DeepEP low-latency inside a CUDA graph and each rank dispatches at most SGLANG_DEEPEP_NUM_MAX_DISPATCH_TOKENS_PER_RANK tokens per step (default 128, at most 1024). Keep --cuda-graph-max-bs-decode × the tokens per request (1, or --speculative-num-steps + 1 with ECHO, or the block size + 1 with DSpark) at or below that value.

3. Advanced Usage

3.1 Completions (Base)

As a base model, ERNIE-5.5-Flash-Base continues text: send prompts to /v1/completions. It has no chat, reasoning or tool-call training, so chat requests, --reasoning-parser and --tool-call-parser do not apply. For few-shot use, put the examples in the prompt and stop at the end of one answer.
Example
Output

3.2 Reasoning (ERNIE-5.5-Flash, coming soon)

ERNIE-5.5-Flash thinks before it answers. Start the server with --reasoning-parser ernie55 (the Reasoning Parser toggle in the Playground above); thinking then lands in reasoning_content and the answer in content. Thinking is on by default; to turn it off for a request, pass enable_thinking: false through chat_template_kwargs (the chat template reads enable_thinking, not thinking).
Example

3.3 Tool Calling (ERNIE-5.5-Flash, coming soon)

Start the server with --tool-call-parser ernie55 (the Tool Call Parser toggle in the Playground above). The parser reads the model’s <ernie:tool_call> blocks, types each argument from the tool’s JSON schema, and returns structured calls in message.tool_calls; streaming emits the arguments as they are generated. Use it together with --reasoning-parser ernie55, since the model reasons before calling a tool.
Example

3.4 HiCache (Hierarchical KV Caching)

Long shared prefixes (system prompts, agent histories) can spill from GPU memory to host memory, and optionally to Mooncake, instead of being recomputed. Add --enable-hierarchical-cache --hicache-ratio 2 for a host tier twice the size of the GPU KV pool (only --hicache-ratio is supported, not --hicache-size). Add --hicache-storage-backend mooncake for an L3 tier, or set it from the HiCache card in the Playground above.

3.5 Speculative Decoding

ECHO. The checkpoint carries one ECHO layer after the main stack: the backbone’s own final layer, trained to predict future tokens, doubles as the draft. Turn it on with --speculative-algorithm EAGLE (or NEXTN; the ECHO options in the Playground above). The layer was trained for one future token and can draft several steps (--speculative-num-steps). The attention backend supports chain drafts only, so keep --speculative-eagle-topk 1; --speculative-num-draft-tokens then follows as --speculative-num-steps + 1 (the defaults are 1, 1 and 2). Measured on GSM8K at batch size 1 with greedy decoding, the mean accept length is 1.93 / 2.28 / 2.36 tokens per step for 1 / 2 / 3 draft steps, with unchanged accuracy; 2 steps take most of the gain. DSpark (ERNIE-5.5-Flash, coming soon). The ERNIE-5.5-Flash checkpoint bundles a DSpark draft, served with --speculative-algorithm DSPARK together with --enable-dp-lm-head (the DSpark option in the Playground above, with --model-path set to baidu/ERNIE-5.5-Flash). The draft path defaults to the model path and the block size comes from the checkpoint. DSpark under attention DP fails to start without --enable-dp-lm-head; without attention DP the flag is ignored, so always pass it. The Base checkpoints carry no DSpark draft.
Command

3.6 PD Disaggregation

Pick the Prefill role / Decode role in the PD Disagg card of the Playground above (Mooncake transfer). With speculative decoding, pass the same speculative flags to the prefill and decode servers. With DeepEP, run decode with --deepep-mode auto (the default) so it replays CUDA graphs; under --deepep-mode normal decode runs eagerly.
Parallel sampling (n > 1 in one request) currently hangs under PD disaggregation: the n sub-requests share one bootstrap room. Send n = 1 requests to a PD deployment.